Reorganized core/ directory, it was too fatty already

-Removed FuncRef, since Callable makes it obsolete
-Removed int_types.h as its obsolete in c++11+
-Changed color names code

modules/mono/csharp_script.cpp

@@ -33,6 +33,7 @@
 #include <mono/metadata/threads.h>
 #include <stdint.h>
 
+#include "core/config/project_settings.h"
 #include "core/debugger/engine_debugger.h"
 #include "core/debugger/script_debugger.h"
 #include "core/io/json.h"
@@ -40,7 +41,6 @@
 #include "core/os/mutex.h"
 #include "core/os/os.h"
 #include "core/os/thread.h"
-#include "core/project_settings.h"
 
 #ifdef TOOLS_ENABLED
 #include "editor/bindings_generator.h"